Isaac Newton came up with a way to study color at the ripe age of 23. In the year 1666, Newton came up with what is known as the Newton Color Circle. This circle
Credit to heasarc.nasa.gov
summarized the “additive mixing properties of color”. The circle worked by having the primary colors of red, green, and blue. Then across from those colors are their complementary colors, which would then be placed across from the primary colors. This ends with the colors placed in order based on their wavelengths. Newton also thought up the idea that sunlight, or what is also known as white light, is the combination of all the colors of the color spectrum. Newton ended up proving this idea or theory true by doing an experiment showing the dispersion of light with the use of glass prisms. Next came Thomas Young, who in 1802 came up with the idea that the eye has three receptors for color. Then came James Clerk Maxwell, who did research on the three primary colors of red, green, and blue. Maxwell found out that the hue plus the saturation of the color that someone sees is insensitive to that said colors brightness. Hermann von Helmholtz put the idea that Young came up with and did more work to prove what Young stated was true. This led to the theory of the eye having three color receptors being called the Young-Helmholtz Theory. There were experiments in 1920 over the primary colors of red, green, and blue to see if the colors could match a gamut, or visual colors pertaining to a particular range. In 1965, more in depth experiments were conducted on Young’s theory of the eye having three color receptors. These experiments would further prove Young’s theory true that the eye does have three color receptors. In 1931, there was a system invented to measure color in a quantitative way by using a coordinate plane. The name of this system is the CIE chromacity diagram. CIE stands for the Commission International de l’Eclairage. There were some problems on the system, and in 1976 a new system was released, but this new system did not gain favor and the 1931 CIE chromacity diagram is still in use today.[1][2]
What is color?
Color is a product of a humans visual perception. The color one sees when looking at an object is because it is absorbing all light and reflecting the color that it is. For example, a banana looks yellow because it is absorbing all light except for
yellow light, the latter which it is absorbing. When an object reflects all light, humans perceive that object as white and vice versa for black, meaning an object that absorbs all light would be perceived as black.[3]
The Visible Spectrum
Credit to www.uvabcs.com
All color that humans can see are part of what is known as the visible spectrum. An average human can see 390 - 750 nanometers. The colors that lie on the visible spectrum can be remembered as ROY G BIV, or red, orange, yellow, green, blue, indigo, and violet. Although, indigo is sometimes excluded from the visible spectrum. Isaac Newton was the first human to actually define the visible spectrum. Newton did this by using a glass prism and when light passed through it, the light got separated into what we now know as the color spectrum. There is some speculation that Newton only included indigo in the spectrum to make the number of colors seven, matching that of the number of notes in a music scale. Red is visible from 650 to 800 nanometers, orange from 590 to 640 nanometers, yellow from 550 to 580 nanometers, green from 490 to 530 nanometers, blue from 460 to 480 nanometers, indigo from 440 to 450 nanometers, and violet from 390 to 430 nanometers.[4]
How we see color
There are two ways in which humans process color. Humans process color with their eyes and brain.
The way we process color is a very complex process. Out of our five senses: sight, smell, hearing, touch, and taste; sight has been found to take part in 80% of information we take in. This can be proven by when humans associate colors with taste. For example, say when one eats brown ice cream, the brain naturally thinks it would be chocolate flavored and even if it tastes like strawberries instead
the brain still wants to believe it tastes like chocolate instead. When we process light with out eyes, it first passes through our cornea, which has been described as a window. After the cornea, is the iris. The iris is the part of a human eye that gives are eye color, as in the color of one’s eye. It is the color of one’s iris that is the color of one’s eye. There is a hole in the middle of the iris, and it is known as the pupil. The job the pupil does is to determine the amount of light that passes into the eye. The reason our pupil’s dilate is because of the iris, which makes the pupil enlarge and shrink. Our pupil’s appear black because it absorbs light and does not reflect any of it back out. There are some situations where our pupil does in fact reflect light. Past the pupil is the lens. The lens in our eyes focus light behind our eye. Behind the lens, or rather covering the lens is the retina. The retina contains photoreceptor nerve cells that “convert rays (photons) of light into correspond
ing electrical signals”. Our eyes process these signals and are then passed down the optic nerve which leads to the brain. In fact the retina itself has been referred to as actually being apart of the human brain.[5][6]
Problems with seeing color
Color blindness is a problem in which humans have trouble seeing color to a certain degree. This does not necessarily mean the person can not see color at all. There are mild forms of color blindness. Color blindness is mostly hereditary,
Credits to rlv.zcache.com
meaning it is passed on from parents to child. Color blindness could also happen from a disease in the eye, old age when the lens has darkened, and damage to one’s retina. Color blindness occurs when cones in one’s eyes are not able to tell the difference between certain wavelengths. In the eye, there are 3 cones: one for short wavelengths, one for medium wavelengths, and one for long wavelengths. Longer wavelengths are ones involving shades of the color red, medium wavelengths are one involving shades of green, and short wavelengths are for the color blue. There are different types of color blindness. Two categories to separate color blindness could be inherited, as in at birth, or acquired, as in throughout time. The three different types of hereditary color blindness is monochromacy, dichromacy, and anomalous trichromacy. When a human has monochromacy that means that person is known as being totally color blind. This means they can not tell the difference between a
ny color. The condition of monochromacy happens when one is missing two or even all three of their cones in their eye. There are two types of monochromacy, they are rod monochromacy and cone monochromacy. Dichromacy is when one is missing one of the three cones in one’s eye. Dichromacy is not as severe as monochromacy. Dichromacy is hereditary, and is more common in males than females. There are three types of dichromacy. They are protanopia, deuteranopia, and tritanopia. Protanopia is the absence of the cone that lets on see longer wavelengths, also known as the red cone. Protanopia is hereditary and makes one see the color red as completely black. Deuteranopia is also hereditary, but is instead when one is missing the cone that lets one distinguish medium wavelengths, also known as the green cone. Tritanopia is extremely rare and is when the cone that distinguishes short wavelengths, or the blue cone. The third type of inherited color blindness is anomalous trichromacy. There are three types of anomalous trichromacy. Out of the three types of inherited color blindness, anomalous trichromacy is the most common type. Trichromacy is defined as normal three coned vision. Thus making anomalous trichromacy, an anomaly or problem with a cone. Protanomaly is a type of anomalous trichromacy where the sensitivity of the longer wavelength red cone changed, making it hard for one to tell the difference between shades of red and green. Deuteranomaly is caused by a change in the sensitivity of the medium wavelength green cone. Deuteranomaly is like protanomaly in that it makes it hard for the affected person to tell the difference between shades of red and green, except that it is easier for one with deuteranomaly to distinguish red and green shades than one with protanomaly. Deuteranomaly is known as the most common type of color blindness in humans. The last type of anomalous trichromacy is tritanomaly. Tritanomaly is when the short wavelength blue cone’s sensitivity is changed, making it hard to tell the difference between shades of blue and yellow. Out of the three types of anomalous trichromacy, tritanomaly is the most rare. Also unlike the other two types of anomalous trichromacy, tritanomaly is not sex linked, meaning it can be present in females as well as males.[7]
Rainbows
he main concept of physic that causes a rainbow is the process of refraction. Refraction is the process in which light bends because it is traveling through a different medium. The reason it bends is because light travels at
Credits to images2.layoutsparks.com
different speeds in different mediums. When light travels through a prism, it refracts or bends. Different colors move at different speeds due to their different frequencies, so when they pass through a prism of glass to air, the different colors will bend at different angles.
This makes the colors look separated like in a rainbow. Rainbows have this same effect because raindrops can have the same effect that a glass prism has. When sunlight, or white light, hits a group of raindrops at a precise angle, one will be ab
le to see the color spectrum of ROY G BIV, or red, orange, yellow,green, blue, indigo, and violet, in other words a rainbow. What we see when we look at a rainbow is not one individual raindrop. It is a group of raindrops. Each band of color we see when looking at a rainbow is different raindrops. This is because the colors can only be seen at certain angles and different raindrops are in different positions, so we see the colors refracting from a whole group of different raindrops. Rainbows are actually full circles. We usually see rainbows as only a semicircle or arc due to us being on the ground. To see the rainbow as a full circle, one would actually have to be higher than the rain and be looking down on it. A special phenomenon of rainbows is the double rainbow. When one sees a double rainbow there is usually a darker one and a more faded one. The darker or more visible rainbow happens the same way as any other ordinary rainbow, the one that is different is faded, less visible second rainbow. The faded, less visible second rainbow occurs due to light. The light when traveling through the raindrops reflects not once but twice, this causes the second rainbow that is less visible and a little bit above the more visible rainbow. An extra tidbit is that if one were to actually look at the faded rainbow, one would see that the colors are opposite that the more visible one. Basically rainbows are just a combination of light and water under the right circumstances. There is another type of rainbow known as a lunar rainbow. It is a its name states, a rainbow that occurs because of moonlight. In order for this to happen there has to be a full moon outside. A full moon is bright enough to produce the same effect the sun does on raindrops. Lunar rainbows, however, are not as bright as their counterparts, rainbows that are produced by sunlight, because sunlight is brighter than moonlight.[8]
Table of Contents
Colors
History of Color
Isaac Newton came up with a way to study color at the ripe age of 23. In the year 1666, Newton came up with what is known as the Newton Color Circle. This circle
What is color?
Color is a product of a humans visual perception. The color one sees when looking at an object is because it is absorbing all light and reflecting the color that it is. For example, a banana looks yellow because it is absorbing all light except for
yellow light, the latter which it is absorbing. When an object reflects all light, humans perceive that object as white and vice versa for black, meaning an object that absorbs all light would be perceived as black.[3]
The Visible Spectrum
All color that humans can see are part of what is known as the visible spectrum. An average human can see 390 - 750 nanometers. The colors that lie on the visible spectrum can be remembered as ROY G BIV, or red, orange, yellow, green, blue, indigo, and violet. Although, indigo is sometimes excluded from the visible spectrum. Isaac Newton was the first human to actually define the visible spectrum. Newton did this by using a glass prism and when light passed through it, the light got separated into what we now know as the color spectrum. There is some speculation that Newton only included indigo in the spectrum to make the number of colors seven, matching that of the number of notes in a music scale. Red is visible from 650 to 800 nanometers, orange from 590 to 640 nanometers, yellow from 550 to 580 nanometers, green from 490 to 530 nanometers, blue from 460 to 480 nanometers, indigo from 440 to 450 nanometers, and violet from 390 to 430 nanometers.[4]
How we see color
There are two ways in which humans process color. Humans process color with their eyes and brain.
The way we process color is a very complex process. Out of our five senses: sight, smell, hearing, touch, and taste; sight has been found to take part in 80% of information we take in. This can be proven by when humans associate colors with taste. For example, say when one eats brown ice cream, the brain naturally thinks it would be chocolate flavored and even if it tastes like strawberries instead
the brain still wants to believe it tastes like chocolate instead. When we process light with out eyes, it first passes through our cornea, which has been described as a window. After the cornea, is the iris. The iris is the part of a human eye that gives are eye color, as in the color of one’s eye. It is the color of one’s iris that is the color of one’s eye. There is a hole in the middle of the iris, and it is known as the pupil. The job the pupil does is to determine the amount of light that passes into the eye. The reason our pupil’s dilate is because of the iris, which makes the pupil enlarge and shrink. Our pupil’s appear black because it absorbs light and does not reflect any of it back out. There are some situations where our pupil does in fact reflect light. Past the pupil is the lens. The lens in our eyes focus light behind our eye. Behind the lens, or rather covering the lens is the retina. The retina contains photoreceptor nerve cells that “convert rays (photons) of light into correspond
ing electrical signals”. Our eyes process these signals and are then passed down the optic nerve which leads to the brain. In fact the retina itself has been referred to as actually being apart of the human brain.[5] [6]
Problems with seeing color
Color blindness is a problem in which humans have trouble seeing color to a certain degree. This does not necessarily mean the person can not see color at all. There are mild forms of color blindness. Color blindness is mostly hereditary,
ny color. The condition of monochromacy happens when one is missing two or even all three of their cones in their eye. There are two types of monochromacy, they are rod monochromacy and cone monochromacy. Dichromacy is when one is missing one of the three cones in one’s eye. Dichromacy is not as severe as monochromacy. Dichromacy is hereditary, and is more common in males than females. There are three types of dichromacy. They are protanopia, deuteranopia, and tritanopia. Protanopia is the absence of the cone that lets on see longer wavelengths, also known as the red cone. Protanopia is hereditary and makes one see the color red as completely black. Deuteranopia is also hereditary, but is instead when one is missing the cone that lets one distinguish medium wavelengths, also known as the green cone. Tritanopia is extremely rare and is when the cone that distinguishes short wavelengths, or the blue cone. The third type of inherited color blindness is anomalous trichromacy. There are three types of anomalous trichromacy. Out of the three types of inherited color blindness, anomalous trichromacy is the most common type. Trichromacy is defined as normal three coned vision. Thus making anomalous trichromacy, an anomaly or problem with a cone. Protanomaly is a type of anomalous trichromacy where the sensitivity of the longer wavelength red cone changed, making it hard for one to tell the difference between shades of red and green. Deuteranomaly is caused by a change in the sensitivity of the medium wavelength green cone. Deuteranomaly is like protanomaly in that it makes it hard for the affected person to tell the difference between shades of red and green, except that it is easier for one with deuteranomaly to distinguish red and green shades than one with protanomaly. Deuteranomaly is known as the most common type of color blindness in humans. The last type of anomalous trichromacy is tritanomaly. Tritanomaly is when the short wavelength blue cone’s sensitivity is changed, making it hard to tell the difference between shades of blue and yellow. Out of the three types of anomalous trichromacy, tritanomaly is the most rare. Also unlike the other two types of anomalous trichromacy, tritanomaly is not sex linked, meaning it can be present in females as well as males.[7]
Rainbows
he main concept of physic that causes a rainbow is the process of refraction. Refraction is the process in which light bends because it is traveling through a different medium. The reason it bends is because light travels at
This makes the colors look separated like in a rainbow. Rainbows have this same effect because raindrops can have the same effect that a glass prism has. When sunlight, or white light, hits a group of raindrops at a precise angle, one will be ab
le to see the color spectrum of ROY G BIV, or red, orange, yellow,green, blue, indigo, and violet, in other words a rainbow. What we see when we look at a rainbow is not one individual raindrop. It is a group of raindrops. Each band of color we see when looking at a rainbow is different raindrops. This is because the colors can only be seen at certain angles and different raindrops are in different positions, so we see the colors refracting from a whole group of different raindrops. Rainbows are actually full circles. We usually see rainbows as only a semicircle or arc due to us being on the ground. To see the rainbow as a full circle, one would actually have to be higher than the rain and be looking down on it. A special phenomenon of rainbows is the double rainbow. When one sees a double rainbow there is usually a darker one and a more faded one. The darker or more visible rainbow happens the same way as any other ordinary rainbow, the one that is different is faded, less visible second rainbow. The faded, less visible second rainbow occurs due to light. The light when traveling through the raindrops reflects not once but twice, this causes the second rainbow that is less visible and a little bit above the more visible rainbow. An extra tidbit is that if one were to actually look at the faded rainbow, one would see that the colors are opposite that the more visible one. Basically rainbows are just a combination of light and water under the right circumstances. There is another type of rainbow known as a lunar rainbow. It is a its name states, a rainbow that occurs because of moonlight. In order for this to happen there has to be a full moon outside. A full moon is bright enough to produce the same effect the sun does on raindrops. Lunar rainbows, however, are not as bright as their counterparts, rainbows that are produced by sunlight, because sunlight is brighter than moonlight.[8]
Presentation
References